jason 2020-09-14 16:36
致精进的你:
ρ(U1,U2)=COV(U1,U2)/ [σ(U1)^2*σ(U2)^2]=COV(0.12F+(√1-0.12^2)Z1,0.7F+(√1-0.7^2)Z2)/ [σ(0.12F+(√1-0.12^2)Z1)^2*σ(0.7F+(√1-0.7^2)Z2)^2],最终推导得出ρ(U1,U2)=0.12*0.7=0.084,这类题目比较少见,不用过度纠结
The real talent is resolute aspirations.
真正的才智是刚毅的志向。